HELP!!!!! www.lop.com

i don't know how it's happened, but it seems my IE6 has been hacked by the site www.lop.com. everytime a web address is entered that is wrong, instead of showing the standard 'address not found' page, it is automatically redirecting to lop.com.

Also, i've just sorted out all my favorites folder again after lop.com put loads of unwanted crap in there like adult stuff etc...

anyone know how to get rid of this annoying hack? i can't reinstall (or don't know how to) IE6, and i'm wondering whether a full reformat will be the only solution??

thanks for any help

PS: don't go anywhere near www.lop.com if u want nothing less than bother!